Placing label over mapped 3D graph in Gnuplot

I want the below desired effect

I am using a gnuplot script similar to this

reset
set term postscript eps enhanced "Helvetica" 30
set size square
set xlabel "X position"
set ylabel "Y position"
set pm3d map
set palette rgbformulae 22,13,-31
set xrange [0 : 22.0000000000]
set yrange [0 : 17.0000000000]
set zrange [0 : 0.1614027105]
set xtics 5
set ytics 0,4
set cbtics 0,0.020
set style line 1 lw 1
unset key
set dgrid3d 45,45
set style line 1 lt 1
set hidden3d
splot "data.data" u 1:2:3
set label "98.8" at 9,-2 textcolor lt 1
set label "1.2" at 9,6 textcolor lt 1

But when I do, the labels (98.8, and 1.2) don't get printed. If I provide a bogus data.data file, lets say with only a single (x,y,z) point, then nothing gets graphed and I can see the labels. Therefore, I am guessing that my graph is occluding my labels. How do I get the labels to be printed on top of my graph?